The headbanging collisions that thrill sports fans have lifelong effects on the athletes, with impairments in movement and thinking skills showing up 30 years or more after the concussions, researchers reported Tuesday. The slight deficits resulting from one or two concussions were similar to problems found in patients with the early stages of dementia, although they did not interfere with the daily life of the otherwise healthy men, researchers reported in the journal Brain.

Republican Sen. Pete V. Domenici of New Mexico, one of the most influential voices in Congress on budget and energy issues, announced Thursday that he would retire at the end of his term because of a degenerative brain disease. "I come here today, to the site of the school that I attended as a boy, to tell you that I will not run for reelection to the United States Senate," Domenici said at a news conference in Albuquerque. He is serving his sixth term.

Mad cow disease and other related brain disorders may be caused by a virus and not the weird, misshapen proteins, known as prions, that scientists think are responsible, according to a study released Monday. Researchers reported that they found virus-like particles in mouse nerve cells infected with two brain-wasting diseases similar to mad cow disease, but found no traces of the particles in uninfected cells. Lead author Dr.

The U.S. Department of Agriculture said Monday that a cow from an Alabama dairy farm had tested positive for mad cow disease, the third U.S. case of the bovine brain-wasting syndrome. The stricken animal was tested for bovine spongiform encephalopathy, or BSE, because it was a "downer," an animal that couldn't walk. The cow posed no risk to public health because it wasn't sent to a food processing plant, officials said.

A Los Angeles Superior Court judge whose competency was questioned by a state commission because he allegedly suffered from a degenerative brain disease has retired, officials said Friday. A hearing on Judge Rodney E. Nelson's competence was scheduled for Monday by the Commission on Judicial Performance, an independent state agency charged with investigating complaints of judicial incapacity and misconduct.

The two pharmaceutical companies that make the drug Tysabri said they had found no new cases of a rare brain disease among nearly 1,500 people who took the suspended drug to treat rheumatoid arthritis and Crohn's disease. Elan Corp. of Dublin, Ireland, and Biogen Idec Inc. of Cambridge, Mass., said their screening of people who took Tysabri in clinical trials for both diseases had turned up no new cases of progressive multifocal leukoencephalopathy.

From the moment Joan Kingsford first saw her husband stagger in his welding shop three months ago, she wanted two things: his recovery and to know what had made him sick. She didn't get either. Six doctors and several weeks later, Alvin Kingsford, 72, died. Doctors suspect sporadic Creutzfeldt-Jakob disease. The fatal brain-wasting illness can only be conclusively diagnosed with an autopsy.

MAD cow-type diseases are insidious. The fatal brain disorders can incubate for decades before symptoms appear, yet there is no way to test a live animal, or human, for them. Because a diagnosis can only be made after death, diseased animals with no obvious symptoms can enter the food chain, infecting other animals or people, and humans with the diseases can be misdiagnosed or infect others through blood or organ donations.

Lorenzo's oil -- a dietary supplement concocted by Virginia parents in a last-ditch effort to save their son's life -- appears to delay the effects of a rare genetic disease in young boys if taken early and in concert with a low-fat diet, according to the first long-term study of the treatment reported today in the Archives of Neurology. The study followed 89 boys who had the genetic mutation for childhood cerebral adrenoleukodystrophy, and found that 74% of them remained healthy after 13 years.

Meat safety regulations aimed at reducing the risk of mad cow disease will be particularly disheartening for those Latinos whose culinary favorites include tacos filled with brain and small intestines, soup with bits from the spinal cord and, at holiday times, the whole head of a cow. The rules, imposed after the Dec. 23 disclosure of the first case in the U.S. of mad cow disease, prohibit the sale of skulls, brains, eyes, vertebrae and spinal cords from cattle more than 30 months old.